IBNHIBBAN 5213:
from al-Qāsim b. ʿAbd al-Raḥman b. ʿAbdullāh b. Masʿūd from his father from his grandfather —
[Machine] The Messenger of Allah ﷺ said, "Whoever forgets to mention Allah's name at the beginning of his meal, let him say it when he remembers, 'Bismillah' (In the name of Allah) at the beginning and at the end. For indeed, he will have a new meal and he will be protected from any impurities that may have been present."
ابن حبّان ٥٢١٣:
عن القاسم بن عبد الرحمن بن عبد الله بن مسعود عن أبيه عن جده —
قَالَ رَسُولُ اللَّهِ ﷺ «مَنْ نَسِيَ أَنْ يَذْكُرَ اللَّهَ فِي أَوَّلِ طَعَامِهِ فَلْيَقُلْ حِينَ يَذْكُرُ بِسْمِ اللَّهِ فِي أَوَّلِهِ وَآخِرِهِ فَإِنَّهُ يَسْتَقْبِلُ طَعَامَهُ جَدِيدًا وَيَمْنَعُ الْخَبِيثَ مَا كَانَ يُصِيبُ مِنْهُ»
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